Mold



Julie 1,7, 1930. H, A, REDMOND- 1,764,889

MOLD

Filed June '7, 1929 2 Sheets-Sheet 1 MAM ' dbtozmq H. A. REDMOND June 17, 1930.

MOLD

Filed June 7, 1929 2 Sheets-Sheet 2 Harold A.. Hed

(1R01 wat Patented June 17, 1930 UNITED 4sra'rlazs VPA'risN'i oFFlcE HAIBOLIDA A. REDMOND, 0F CINCINNATI, OHIO, ASSIGNOR T0 CINCINNATI, OHIO HARRY J. RATER, 0F

Mom) Application mea :rune 7, 1929.l serial No. 369,135.

My invention relates to molds for casting pistons for internal combustion engines, and more particularly to the cores for such molds.

An important object of my invention is to provide a mold core for use in casting pistons of the split hub type such as disclosed in the pending applications of Stephen D. Hartog, No. 227,705, filed October 21, 1927 and No. 326,832 filed December 18, 1928.

- A further object of my invention is the provision of a mold core which will form a piston with a cast in hub slot or split.

The present invention is4 adapted for use in a mold of the type described in Owen et al.

No. 1,538,584ofMay 19, 1925, Schnobrich No.

1,525,893 of February 10, 1925 vand Rindsberg No. 1,648,194 of November 8, 1927.

Other objects and advantages of my invention will be apparent during the course of the 2o following description.

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` In the accompanying drawings, which form a part of this specification and wherein like characters of reference denote like or corresponding parts throughout the same,

Figure 1 is a vertical section through a split hub piston adapted to be cast by my improved mold core,

Figure 2- is a transverse sectional view thereof,

Figure 3 is a longitudinal sectional view of a piston mold showing the relation of the core sections to the other parts of the mold,

Figure`4 is a front elevation of the assembled core members,

Figure 5 is a side elevation thereof,

Figure 6 is a vertical sectional view on the line 6-6 of Figure 4,

Figure 7 is a front elevation of one of tli'e and skirt by a strut 12 and secured at the other end to the skirt by a strut 13. The hubs are Split at 14 between the struts 12 and the struts 13 to form an opening completely separating the inner ends of the hubs from vthe outer ends thereof. Reinforcements 15 are arranged on the inner faces of the struts 13, and reinforcement ribs 16 are located onthe interior of the head of the piston. This type of piston is clearly described in the Hartog applications referred to above and need not be described in detail here.

, In Figure 3 I have illustrated a piston mold similar to that described in the mold patents referred to above. This mold comprises the usual separable mold sections 17 mounted on the base plate 18. The meeting faces of these sections `are so shaped las to form a mold cavity 19.

Core pins 2O extend through the mold sections and into the mold cavity. The pins 20 are slidably arranged in the mold sections and are moved into and out of the mold cavity by means of rack 21 and pinions 22. The core 23 is made up of a series of sections rWhich 'extend down into the mold cavity and which dsections are the main or center section 25, the

intermediate sections 26, two in nulnber, and the two outer or' end sections 27. The center section 25 has a transverseextension 28 at its upper end of the same Width as the rest of the section and adapted to extend over the tops of the mold sections. The intermediate sections 26 are ofthe same length as the center sec- .tion 25 and also have transverse extensions 29 at their upper ends. The extensions 29 are shorter than the extension 28 and kextend out! wardly from-the sections 26 to form trans. verse ledges or ange's 30 at the "top of the sections, such ledges terminatingwellshort of the bottom of the extensions 28 and 29.

The outer sections 27 extend to the under side of the flanges or ledges 30 against which they abut. The sections 27 are provided at their tops with extensions 31 which 4extend to theends of the extension 29 and pro]ect outwardly beyond the faces of the l/edges 30 to lap over the tops of the mold sections along their entire length.

The u per end of the center section is proi vided with centrally arranged ribs or keys 32 which extend from the top of the section down its center for about one-third of its "length The inner faces of the intermediate sections 26 are provided with grooves or keyways 33 which engage the keys 32 and prej vent lateral movement of the sections 26 with.

respect to the V usual.

The five sections cooperate to form a corewhich is substantially circular in .outline to it within the mold cavity 1,9. A shoulder 35 .narks the bottom of the piston skirt, the piston being cast in inverted position, and the shape of the interior of the piston is deterv ranged in the blades at a point corresponding f reare braced thereby.

mined by theshape of the lower ends of the core sections. The intermediate sections 26 'ire provided with depressions 36 for forming the piston pin hubs, and less shallow depressions 37 define the struts 13 of the piston. Grooves 38 may be provided for forming the reinforcing-ribs 15 on the ,struts` 13.

Where the hubs are tozbe split, the core members will only form the inner half of each piston pin hub, together with its struts, and the outer half of The lower ends of the core sections will, therefor, project beyond the portions of the core Vsections. adjacent the depressions 36 and 37 as at 39. 'A straight, horizontal shoulder 4Q is formed below the depressions 36 and 37 on each-section 26, and a fiat surface 41 isy interposed between the shoulder 40 and the depresslons. A A

The outer sections proper terminate at the top of the depressions 36, but are formed with knife or blade like extensions 42, the inner faces of which are continations of the inner faces of th sections 27 and the outer faces of which. are inclined to form the downwardly tapering knife like extensions 42. The blades 42 bridge the depressions 36 and 37 and abut at their lower ends against the shoulders 40. The side edges of the blades 42 are also downwardly inclined, and the -blades are therefor narrowe at their lowervends. than at their upper ends. Circular openings u43 are ar.

to the centers of the de ressions 36 and ceive'the core pins 20 which extend through the operiings 43 and abut against the inner walls of the depressions 36.

It will be seen that the sections 27 are snugly received between the ledges 30 and the shoulders 40 and that the lower ends of'the blades 42 rest against the flat surfaces 41 and bled in the mold cavity each hub with its associated .l struts will be formed by the mold sections 17.

members are assemthe center section to be put into posltion, and the In operation the core being the last metal is poured into the mold cavity. The

piston will be cast as usual, but because of -the blades 42, there will be an opening 14 completely separating the two ends of each piston pin hub. Although the blades 42 are relatively thin, they are so supported that the heat from the molten metal will not cause them to warp or to otherwise get out of shape. When the casting has cooled, the center sec- Ition is removed, and the intermediate sections are then removed, one at atime, through the space left vacant by the center section. The'end sections are then lifted out, after the core pins 2O have .been withdrawn, and this operation is easily accomplished by reason o the tapering shape lof the knife-like blades 4,2.

It will be seen that by the use of my improved core member, split hub pistons may as can the' usual type of piston, and no cutting is required after casting, to produce the Split 14.

While I have shown and described the preferred embodiment of my invention, it is to befunderstood that various changes in the size, shape and arrangement of parts may be resorted to without ,departing from the spirit of my 'invention or the scope of the subjoined claims. i f

Having thus described my invention, what I claim and desire to protect by Letters Patent is e readily cast in one operation, as efficiently i 1. A core for pistonmolds comprising intermediate sections, a center section arranged betweenfthe intermediate sections, means pre-v venting transverse movementof the center section relative to the intermediate sections 'and allowing longitudinal movement of the 'center sectlon, outer core sections and means preventing longitudinal movement of the y outer sections relative to the intermediate sections. y.

2. A core for piston molds comprisin intermediate sections having longitu inal grooves on their inner faces extending to the' upper ends thereof, a center section arranged between the intermediate sections and having ribs engaging the grooves in the intermediate sections, whereby the center section is held againstv movement transversely of the intermediate sections but is capable of movement longitudinally thereof, outer core sections, and members on said intermediate sections engaging the ends of the outer sections to prevent movement of the outer sect-ions longitudinally of the intermediate sectional' 3. A core for piston molds comprisinga body section havingdepressions therein spaced from the bottom thereof, outer core sections and having blade-like extensions lbridgabutting against said body section, L

ing said depressions in the body section, and means for firmly supporting said blade like extensions at the lower ends thereof.

4. A core for piston pin molds comprising a body section having depressions therein spaced from the .bottom thereof, outer core sections abutting against said body section, said outer sections terminating adjacent the upper ends of said depressions and having blade-like extensions bridging said depressions, an-d extending therebelow, and a member on said body portion to engage the lower end of said blade-like extension to secure it in position and brace the same.

5. A core for piston pin molds comprising a body Section hating a depression therein spaced from the bottom thereof, an outer core section abutting against said body section, said outer section terminating in a blade-like extension which bridges the depression and extends therebelow, and means to engage the top of said'outer section and the lower end of said blade-like extension to secure the outer section in position on the body section.

6. A core for piston molds comprising an intermediate section having a groove therein extending to the top thereof, a center section having a rib engaging the groove in the intermediate section, whereby the center section is held against movement transversely of the intermediate section but iscapable of movement longitudinally thereof, an outer core section and members on said intermediate core section to engage the ends of the outer core section to prevent movement thereof longitudinally of the intermediate section.

7. A core for piston molds comprising a body section having a depression therein spaced from the bottom thereof, a fiange adjacent the upper end of the body section, .a 'acent the lower end of the body shoulder ad] section, and an outer core section abutting A against the u nder side of said fiange, and terminating in a blade like extension which bridges said depression in the body section and abuts against the shoulder adjacent the lower end of the body section.

8. A core for piston molds comprising a body section having a depression spaced from its lower end, a flange adjacent the upper end of the body section, a flattened portion arranged below the depression and terminating in a projecting shoulder, an outer core section, v

the upper end of which abuts against the under side of said flange, said outer section terminating in a blade-like extension which bridges the depression and rests against the flattened portion of the body section, the lower end of the blade-like extensions abut'- ting against the shoulder at the lower end of the flattened portion. v

9. A core for a piston mold comprising a body section having a depression spaced from the lower end thereof, a fiange arranged on the upper end of the bodysection, a shoulder arranged below the depression, and an outer core section abutting against said flange at the top of the body section and terminating in a blade-like extension which bridges the depression and abuts against the shoulder therebelow, said blade-like extension tapering from its upper end to its lower end.

10. A core for piston molds comprising a pair of intermediate sections having grooves therein extending to the upper ends thereof, a center section arranged between said intermediate sections and having ribs engaging the grooves therein, said intermediate sections having depressions therein spaced from the bottom thereof, flanges arranged at the upper ends of said intermediate sections, projecting shoulders spaced below said depres-` sions, and outer core sections abutting against the flanges on the intermediate sections, said outer sections terminating in blade-like extensions which bridge said Vdepressions and abut against said projecting shoulders.

11. A core for piston molds comprising a pair of intermediate sections having grooves therein extending to the upper ends thereof, a center section arranged between said intermediate sections and having ribs engaging the grooves therein, tions having depressions' therein spaced from the bottom thereof, flanges arranged at the upper ends of said intermediate sections, projecting shouldersspaced below said depressions, and outer core sections abutting against the flanges on the intermediate sections, said outer sections vterminating in blade-like extensions which bridge said depressions and abut against said projecting shoulders, said extensions tapering from their upper ends to their lower ends.

12. A core for piston molds comprising a pair of intermediate sections having grooves said intermediate sectherein extending to the upper ends thereof, a

bottom thereof, flanges arranged at the uppery ends of' said intermediate sections, projecting shoulders spaced below said depressions, and outer core sections abutting against the flanges on the intermediate sections, said outer sections terminating in blade-like extensions which bridge said depressions and abut against said projecting shoulders, said extensions tapering from their upper ends to their lower ends and being provided with circular openings to receive sliding core pins.

13. The method of casting a piston having a piston pin hub which consists in inserting a thin core blade in that portion of the piston mold which forms the piston pin hub, and castinr the piston around said core blade, whereby a piston .is formed having a split piston pin hub. i

14. The method of casting a piston having piston pin hubs which consists in inserting thin tapered core the piston mold which form the piston pin hubs, and casting said piston around said core blades whereby a. oiston is formed having piston pin hubs separated into independent portions by slits formed by said core blades.

In testimony whereof I aix signature.

m HAROLD A. REMOND.

blades in those portions of- 

